Pfizer’s COVID-19 vaccine does not contain fetal cells, contrary to online claims
CLAIM: Newly leaked emails among Pfizer employees show that the company’s COVID-19 vaccine contains fetal cells.
AP’S ASSESSMENT: False. The emails cited say that the vaccine was tested, not produced, using a cell line that originated with a fetus in the 1970s. That information was already publicly available.
THE FACTS: A widely shared video by the group Project Veritas has led to a false claim online that purported emails among Pfizer officials show that the pharmaceutical company’s COVID-19 vaccine contains aborted fetal cells.
But the video — an interview between Project Veritas founder James O’Keefe and a self-identified Pfizer employee who claims to show internal emails from the company — does not support that erroneous conclusion.
Instead, it shows that the company used a fetal cell line when testing the efficacy of its vaccine. Cell lines, which are key to medical research, are cloned copies of cells from the same source that have been adapted to grow continuously in labs.
Nevertheless, users spread the falsehood about the contents of the vaccine widely on social media with references to religious exemptions.
“You are mandated to inject dead babies into your body,” one Twitter account sharing the video falsely claimed. “Fetal cells in the vaccines yet they are denying people religious exemptions.”
A Facebook post citing the video made the false allegation that Pfizer had “failed to disclose the use of several aborted fetal cell lines, including the HEK 293 (from experiment 293) used in the research, development and production of their vaccine. They don’t want the public to know they used cells from aborted fetuses, so that your religious exemptions are denied.”
At the heart of the widely shared video spurring the false claims are purported emails among Pfizer officials from early 2021. The messages displayed show an alleged conversation about the company’s reluctance to publicize that testing of its vaccine — not production — used a cell line that was originally derived from fetal tissue.
One of the main emails cited specifically says, “Human fetal derived cell lines are not used to produce our investigational vaccine, which consists of synthetic and enzymatically produced components.” It adds: “One or more cell lines with an origin that can be traced back to human fetal tissue has been used in laboratory tests associated with the vaccine program.”
The video also shows an email referencing the HEK293T cell line — or Human Embryonic Kidney 293 — which was first established in the early 1970s using cells from a kidney of a fetus.
In a paper published in September 2020 detailing the vaccine’s development and success in mice and monkeys, Pfizer and BioNTech scientists said that the vaccine had been tested using the HEK293T cell line.
And the United States Conference of Catholic Bishops in a January document about the COVID-19 vaccines noted: “Neither Pfizer nor Moderna used an abortion-derived cell line in the development or production of the vaccine. However, such a cell line was used to test the efficacy of both vaccines.”
The conference recommended that, in the absence of a vaccine with no connection at all to such a cell line, vaccines that use them “only for testing would be preferable to those that use such cell lines for ongoing production.”
“There are no components of fetal cells in the vaccine, and none used in manufacturing,” Dr. Saahir Khan, an assistant clinical professor of infectious diseases at the University of Southern California, said in a phone interview about the Pfizer shot.
Khan said it is very common to use such cell lines somewhere along the way in the research or development of vaccines and other medicine for humans. He said such cell lines, started decades ago, are grown in labs — so the cells being used for research are not the original cells.
David Prentice, vice president and research director at the Charlotte Lozier Institute — an anti-abortion think tank that has followed this issue and that is critical of the use of such cell lines — also acknowledged that Pfizer’s vaccine does not contain fetal cells, and that the company used the cell line in question for testing the vaccine only. He repeated a phrase he once heard: “Nothing that goes in my arm ever touched one of those cells.”
One COVID-19 vaccine used in the U.S., from Johnson & Johnson, is produced by using an adenovirus that is grown using retinal cells that trace back to a fetus from 1985, according to the Vaccine Education Center at the Children’s Hospital of Philadelphia. Vaccines for chickenpox and other diseases also use this type of process. But none of these vaccines contain fetal cells.
Pfizer did not respond to questions about the Project Veritas video, but a spokesperson pointed out that information about the testing has been publicly disclosed through a number of sources and news reports.
This is part of AP’s effort to address widely shared misinformation, including work with outside companies and organizations to add factual context to misleading content that is circulating online. Learn more about fact-checking at AP.